CI: Use ubuntu-18.04 in tests

.github/workflows/cluster_endtoend_11.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (11)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_12.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (12)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_13.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (13)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_14.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (14)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_15.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (15)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_16.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (16)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_17.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (17)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_18.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (18)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_19.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (19)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_20.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (20)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_21.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (21)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_22.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (22)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_23.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (23)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_24.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (24)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_26.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (26)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_27.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (27)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_onlineddl_ghost.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (onlineddl_ghost)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_onlineddl_vrepl.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (onlineddl_vrepl)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_onlineddl_vrepl_stress.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (onlineddl_vrepl_stress)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_vreplication_basic.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (vreplication_basic)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_vreplication_cellalias.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (vreplication_cellalias)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_vreplication_migrate.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (vreplication_migrate)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_vreplication_multicell.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (vreplication_multicell)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/cluster_endtoend_vreplication_v2.yml

@@ -6,7 +6,7 @@ jobs:
 
   build:
     name: Run endtoend tests on Cluster (vreplication_v2)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/endtoend.yml

@@ -4,7 +4,7 @@ jobs:
 
   build:
     name: End-to-End Test
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
     steps:
 
     - name: Set up Go

.github/workflows/unit_race.yml

@@ -4,7 +4,7 @@ jobs:
 
   build:
     name: Unit Test (Race)
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
     steps:
 
     - name: Set up Go

.github/workflows/unit_test_mariadb101.yml

@@ -5,7 +5,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/unit_test_mariadb102.yml

@@ -5,7 +5,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/unit_test_mariadb103.yml

@@ -5,7 +5,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/unit_test_mysql57.yml

@@ -5,7 +5,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/unit_test_mysql80.yml

@@ -5,7 +5,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

.github/workflows/unit_test_percona56.yml

@@ -5,7 +5,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

test/templates/cluster_endtoend_test.tpl

@@ -4,7 +4,7 @@ jobs:
 
   build:
     name: Run endtoend tests on {{.Name}}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go

test/templates/unit_test.tpl

@@ -3,7 +3,7 @@ on: [push, pull_request]
 jobs:
 
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
 
     steps:
     - name: Set up Go